Issue 7                                                                                   October 2001

In this Issue

Welcome

Patent Strike ForceSM

It's Autumn cleanup time.

Interesting Patent Case

Is a two piece assembly the same as a unitary part?

IP Links

IP Glossary


Welcome

This is the seventh issue of Directions, a newsletter from TechRoadmap Inc. discussing intellectual property issues and ideas. We hope to stimulate you to examine and improve your own IP practices. This month's issue addresses that difficult area, the doctrine of equivalents. Feel free to share this newsletter (see copyright notice below) and to provide feedback by e-mail to: bruceahz@techroadmap.com


Patent Strike ForceSM

It's Autumn cleanup time.

Time to pull out your leaf blowers and clean up the yard. And maybe time to clean up your patent claims too. As you do so, you can think about an on-going patent dispute between Toro and White Consolidated Industries. In this suit Toro alleged that White infringed on its 1987 patent by building a competing "convertible vacuum-blower." The problem for Toro is that White's tool does not literally infringe any of Toro's claims. As we know, the courts have long held that there is a doctrine of "equivalents" under which patent protection is extended to cover copies of an invention that include only unimportant and insubstantial changes. Of course, that doctrine begs the question of what is an unimportant or insubstantial change. In the present case, at first blush, it would seem that Toro had a pretty good case; Toro claimed a (air inlet) cover that included a restriction ring to increase blower pressure and White had a separate cover and restriction ring.

Surely, you might say, dividing up a single part into two parts is unimportant or insubstantial. Surprisingly, the District Court disagreed. It held that "a critical function" of Toro's claimed cover was "to automatically insert and remove the restriction ring", that clearly White's two piece apparatus did not perform this function, and therefore White did not infringe. The Appeals Court threw out this finding, pointing out that the actual claim in question said nothing about function and only discussed the structure of the invention. It (the Appeals Court) said a reasonable jury might find that White's two part structure was an insubstantial change from Toro's unitary structure and remanded the case back to the District Court. Although the case is not decided, things are moving in Toro's favor

What lessons can we draw from this case?. Should we get out our vacuum-blowers and clean out all but structural claims from our patents?

Of course, there is no simple rule to follow and all discussions about your claims should always be performed in coordination with your patent attorney, but as always, you are the inventor and you, or someone like TechRoadmap who has worked with you, has the responsibility to communicate what is or is not important to protect in the claims. In doing so you should:

  • Include claims that are broader than "pictures" of your preferred mode - Toro's unitary cover and restriction ring claim was (apparently)  unnecessarily restrictive.

  • Consider functional/means claims in addition to structural claims - it is easier to see the equivalence between two structures if they perform the same, claimed function in substantially the same way.

  • Mentally "design-around" your own claims - and then add claims to improve your patent protection to cover those design-arounds!

Nothing in the preceding article should be construed as legal advice. TechRoadmap Inc serves as an interface between companies and their legal counsel.

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Interesting Patent Case
Is a two piece assembly the same as a unitary part?

 

The Toro Company v. White Consolidated Industries

 

Toro, which owns US patent 4,694,528 for a "convertible vacuum-blower" that is used alternatively to vacuum leaves and small debris or to disperse the same in blower mode, has been asserting that White violated the patent with its vacuum-blower. The dispute hinges on a removable air inlet cover, present in both machines. The cover's primary purpose is to exclude items from reaching the impeller when the machine is used as a blower; the cover is removed for vacuum operation. Toro's '528 accounts for the cover in a claim that reads, in part, "said cover including means for increasing the pressure...." In the Toro machine this "means" is a restriction ring that is integral to the cover, while in the White machine the ring is a separate part.

 

In 1998 Toro won a summary judgment of literal infringement against White. On appeal, the Appeals Court found that literal infringement was not possible since White's cover clearly did not have the restriction ring "permanently affixed to and included as part of the cover". On remand, the District Court issued a summary judgment that there was no infringement under the doctrine of equivalents. The District Court held that "a critical function of the [Toro] air inlet cover...is to automatically insert and remove the restriction ring" (emphasis added) and White's two piece structure, failing to provide this function, was not equivalent.

 

The Appeals Court again disagreed with the District Court's summary judgment. It pointed out that to infringe, an accused device must include an equivalent for each literally absent claim limitation. Further, it pointed out unimportant and insubstantial differences don't count. The Appeals Court clearly felt that a fact finder "might indeed find..." the separation into two components what the patentee has claimed as one to be an insubstantial change.

 

The Appeals Court then focused in on the District Court's use of a function-way-results test ("does substantially the same thing in substantially the same way to get substantially the same result") to find no equivalency. This finding was based on the function of "automatically" placing the restriction ring. The Appeals Court agreed that the automatic insertion of the ring was mentioned as being an "advantageous" function in Toro's specification but the Court strongly stated it was improper to "import into the claim a function from the specification, particularly when the claim recites only purely structural limitations."

 

Finally, the Appeals Court found "Neither the '528 patent's specification nor this court's claim interpretation make the inherent function of automatic placement a key objective of this invention," thereby worthy of differentiating White's two part structure. That is, when a function comes along for the ride its absence cannot be a significant change.  Therefore, the District Court acted improperly to grant summary judgment for White.

 

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IP Links
US Patent office Searchable database of all US Patents and, now, published patent applications.
The Patent Cafe - an on-line source of interesting insights into current IP issues.
EKMS Inc. - a company with whom we've worked that provides a range of IP management services including portfolio analysis, deal-making, and process improvement.

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IP Glossary

Industry's Best Glossary

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